Hanover, Germany – Continental is to start reprocessing PET (polyethylene terephthalate) from recycled bottles into reinforcing fibres for use in its tires as of 2022, the company has announced.
The operation will employ PET recycling technology developed jointly with fibre specialist OTIZ, Oriental Industries (Suzhou) Ltd, according to a 3 Aug release from the German group.
The mechanical process, it said, eliminates the need for intermediate chemical depolymerisation steps and can provide raw materials that match the quality of virgin PET.
“This can completely replace conventional polyester,” stated Continental, noting that the reinforcing yarn will be used in the construction of tire carcasses.
"As early as 2022, we will be able to use material obtained from recycled PET bottles in tire production," said Dr. Andreas Topp, responsible for materials, process development and industrialization in Continental’s Tires business area.
In the “upcycling” process, “the fibres are spun from recycled PET without having to break the material down into its components beforehand,” added Topp.
According to the executive, Continental will present a concept tire with polyester yarn made from recycled PET bottle at this year's IAA MOBILITY in Munich, Germany.
Within the recycling process, the bottles are mechanically shredded melted down and granulated before undergoing solid-state polymerisation and a modified spinning process.
"Our modified manufacturing process enables us to obtain polyester yarn for tire construction from PET bottles without any polymerization process from monomers," explains Dr. Derren Huang, chief of R&D at OTIZ.